Xuan Wang

Aflatoxin B1 (AFB1), one of the most hazardous environmental and foodborne mycotoxins, is a major contributor to the global burden of hepatocellular carcinoma owing to its potent hepatocarcinogenicity and persistence throughout food systems. Although risk assessment and monitoring programs for aflatoxins have been established worldwide, the dynamic patterns of AFB1-related disease burden from production to consumption have been largely overlooked, limiting the development of truly risk-based monitoring strategies. Here, we present an integrated framework that quantifies seasonal and regional occurrence of AFB1 contamination and disease burden, and applies these insights to optimize monitoring strategies under resource constraints. Using official monitoring records of AFB1 and health risk data, our analysis estimated an average burden of 3.51 disability adjusted life years per 100,000 population across China. Interprovincial transfers of peanuts and peanut oil accounted for 52 % more local disease burden than in-province production. By reallocating monitoring batches along these high-risk pathways, the optimized monitoring strategy reduced the national health burden by 25 percentage points relative to current monitoring. Beyond AFB1, our study provides a transferable framework for enhancing mycotoxins management in complex food systems, enabling policymakers to better protect public health under resource constraints.

When designing schemes to help SMEs survive crises, the government typically faces asymmetric information, so that it cannot target the SMEs most worth saving. We show that the government can exploit the information in the borrower loan demand to improve policy targets compared with existing programmes. If the aim is employment protection, optimal policy should fully subsidise the funding cost of only those SMEs whose loan size is below a threshold. If the aim is economic efficiency, the government should target SMEs whose loan size is above a threshold. In general, public policy should utilise private sectors' information and expertise.

The Eurozone Debt Crisis has rekindled the debate on the nexus between currency areas and fiscal sovereigns. After the crisis, much of the intellectual and political debate has been on the benefit of a fiscal union, the idea of creating a common fiscal entity that is well equipped to make state-contingent cross-country transfers within the eurozone. Although the role of a benevolent fiscal union can in theory be welfare-improving for a currency union, it is understood that this is a highly politically constrained option, particularly in the eurozone. Given this constraint, in this chapter, we take the implausibility of fiscal union as given, and argue that debt restructuring can be a close substitute to a fiscal union, leading to welfare improvement. In contrast to a fiscal union that resorts to the government’s visible hand to move nominal resources across countries, the debt restructuring plan designs the bankruptcy rules, but it allows the invisible hand of the markets to make the choice based on context-dependent incentives. Much of the insight in this chapter originates from Goodhart et al. (2018) and Wang (2019). The authors show that debt restructuring is particularly vital in currency unions and can lead to significant welfare improvement for both the debtor and the creditor, given a hard government budget constraint. A wider implication of this chapter is that for the understanding of modern monetary and financial phenomena, particularly the viability of a currency union, we simply cannot ignore the interplay of liquidity and default.

Since the Eurozone Crisis of 2010-12, a key debate on the viability of a currency union has focused on the role of a fiscal union in adjusting for country heterogeneity. However, a fully-fledged fiscal union may not be politically feasible. This paper develops a two-country international finance model to examine the benefits of the bankruptcy code of a capital markets union - in the absence of a fiscal union - as an alternative financial mechanism to improve the welfare of a currency union. When domestic credit risks are present, I show that a lenient union-wide bankruptcy code that allows for default in the cross-border capital markets union leads to a Pareto improvement within the currency union. However, if the union-wide bankruptcy code is too lenient, default may cause the collapse of the capital markets union and impede cross-border risk sharing. Moreover, the absence of floating exchange rates removes a mechanism to neutralise domestic credit risks; I show that softening the union-wide bankruptcy code can recoup the lost benefits of floating nominal exchange rates. The model provides the economic and welfare implications of bankruptcy within a capital markets union in the Eurozone.

The Eurozone Debt Crisis has rekindled the debate on the nexus between currency areas and fiscal sovereigns. After the crisis, much of the intellectual and political debate has been on the benefit of a fiscal union, the idea of creating a common fiscal entity that is well equipped to make state-contingent cross-country transfers within the eurozone. Although the role of a benevolent fiscal union can in theory be welfare-improving for a currency union, it is understood that this is a highly politically constrained option, particularly in the Eurozone. Given this constraint, in this paper, we take the implausibility of fiscal union as given, and argue that debt restructuring can be a close substitute to a fiscal union, leading to welfare improvement. In contrast to a fiscal union that resorts to the government’s visible hand to move nominal resources across countries, the debt restructuring plan designs the bankruptcy rules, but it allows the invisible hand of the markets to make the choice based on context-dependent incentives. Much of the insight in this paper originates from Goodhart, Peiris and Tsomocos (2018) and Wang (2019). The authors show that debt restructuring is particularly vital in currency unions and can lead to significant welfare improvement for both the debtor and the creditor, given a hard government budget constraint. A wider implication of this paper is that for the understanding of modern monetary and financial phenomena, particularly the viability of a currency union, we simply cannot ignore the interplay of liquidity and default.